code: def flatten_sub_graph_namespaces(tf_ssa):
      _flatten_sub_graph_namespaces(tf_ssa, fn_name="main")
  
file_path: turicreate/src/external/coremltools_wrap/coremltools/coremltools/converters/mil/frontend/tensorflow2/tf_graph_pass/rewrite_control_flow_functions.py
imports: from __future__ import print_function
  from __future__ import division
  from __future__ import absolute_import
  import logging
  from coremltools.converters.mil.frontend.tensorflow.parsed_tf_node import ParsedTFNode
  from coremltools.converters.mil.frontend.tensorflow.basic_graph_ops import disconnect_edge, connect_edge, delete_node, replace_node, replace_dest, connect_edge_at_index
label_desc: Use image node_id 12 for calling a global function with example usage: flatten_sub_graph_namespaces(tf_ssa) without return types